Theoretical Physics of Living Matter, Institute for Biological Information Processing and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany.
ACS Nano. 2023 Feb 14;17(3):1935-1945. doi: 10.1021/acsnano.2c05801. Epub 2023 Jan 20.
The transport of particles across lipid-bilayer membranes is important for biological cells to exchange information and material with their environment. Large particles often get wrapped by membranes, a process which has been intensively investigated in the case of hard particles. However, many particles in vivo and in vitro are deformable, e.g., vesicles, filamentous viruses, macromolecular condensates, polymer-grafted nanoparticles, and microgels. Vesicles may serve as a generic model system for deformable particles. Here, we study nonspherical vesicles with various sizes, shapes, and elastic properties at initially planar lipid-bilayer membranes. Using the Helfrich Hamiltonian, triangulated membranes, and energy minimization, we predict the interplay of vesicle shapes and wrapping states. Increasing particle softness enhances the stability of shallow-wrapped and deep-wrapped states over nonwrapped and complete-wrapped states. The free membrane mediates an interaction between partial-wrapped vesicles. For the pair interaction between deep-wrapped vesicles, we predict repulsion. For shallow-wrapped vesicles, we predict attraction for tip-to-tip orientation and repulsion for side-by-side orientation. Our predictions may guide the design and fabrication of deformable particles for efficient use in medical applications, such as targeted drug delivery.
跨脂质双层膜的颗粒运输对于生物细胞与环境进行信息和物质交换非常重要。大颗粒通常会被膜包裹，这一过程在硬颗粒的情况下已经得到了深入研究。然而，许多体内和体外的颗粒都是可变形的，例如囊泡、丝状病毒、大分子凝聚物、聚合物接枝纳米颗粒和微凝胶。囊泡可以作为可变形颗粒的通用模型系统。在这里，我们研究了初始为平面脂质双层膜的各种大小、形状和弹性特性的非球形囊泡。我们使用 Helfrich 哈密顿量、三角化膜和能量最小化，预测了囊泡形状和包裹状态的相互作用。增加颗粒的柔软度会增强浅包裹和深包裹状态相对于非包裹和完全包裹状态的稳定性。自由膜介导了部分包裹囊泡之间的相互作用。对于深包裹囊泡的对相互作用，我们预测会排斥。对于浅包裹囊泡，对于尖端到尖端的取向，我们预测会吸引，而对于侧面到侧面的取向，则会排斥。我们的预测可以为可变形颗粒的设计和制造提供指导，以在医学应用中高效使用，例如靶向药物输送。
